1321734395520 has 512 divisors, whose sum is σ = 5836235673600. Its totient is φ = 274645831680.

The previous prime is 1321734395491. The next prime is 1321734395537. The reversal of 1321734395520 is 255934371231.

1321734395520 is a `hidden beast` number, since 1 + 3 + 2 + 1 + 7 + 34 + 3 + 95 + 520 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 833877 + ... + 1827243.

It is an arithmetic number, because the mean of its divisors is an integer number (11398897800).

Almost surely, 2^{1321734395520} is an apocalyptic number.

1321734395520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1321734395520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2918117836800).

1321734395520 is an abundant number, since it is smaller than the sum of its proper divisors (4514501278080).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1321734395520 is a wasteful number, since it uses less digits than its factorization.

1321734395520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 993413 (or 993395 counting only the distinct ones).

The product of its (nonzero) digits is 680400, while the sum is 45.

The spelling of 1321734395520 in words is "one trillion, three hundred twenty-one billion, seven hundred thirty-four million, three hundred ninety-five thousand, five hundred twenty".